Suspension chain for electroliers and for like electrical purposes



. E. 1. PERRY.

SUSPENSION CHAIN FOR ELECTROLIERS AND FOR LIKE ELECTRICAL PURPOSES.

' APPLICATION FILED NOV- I7, I921.

1,430,402. I n fi p 26, 1922.

2 SHEETS-SHEET I.

. y E. J. PERRY. I SUSPENSION CHAIN FOR ELECTROLIERS AND FOR LIKE ELECTRICAL PURPOSES. f v APPLICATIQN FILED NOV- 11. I921. 51 430 402 PatentedSept. 26, 1922.

2 SHEETS-SHEET 2.

Patented Sept. 26, 19.22.

ETATES SUSPENSION CHAIN FOR ELECTROLIERS AND FOR LIKE ELECTRICAL PURPOSES.

Application filed November 17, 1921. Serial No. 515,902.

T 0 all whom it may concern:

Be it known that I, ERNEST Josnrn PERRY, a subject of the Kingdom of Great Britain, residing'at 68 Heathniill Lane, Birmingham, England, have invented certain new and useful Improvements in or Relating to Suspension Chains for Electroliers and for like Electrical Purposes (for which I have filed application for patent in Great Britain #550,685, October 80, 1920), of which the following is a specification.

This invention comprises certain improvements in or relating to suspension chains for electroliers and for like electrical purposes wherein a chain is employed to suspend a lamp or lamps and to con vey the electric leads thereto.

ore particularly the invention relates to suspension chains of the'type in which alternate links are of externally grooved formation so as to provide a means of protecting and partly enclosing and concealing the leads which are passed around them on opposite sides for threading and crossing through the intermediate complementary links.

In this type of suspension chain the said intermediate links haveordinarily been of a plain or ungrooved form affording only a limited protection for the leads.

The object of the present invention is to provide a suspension chain of this type in which the crossed and interthreaded leads are more effectively protected and partly enclosed and concealed, and in which provision is made for more readily and economically lengthening or shortening the chain than has hitherto been possible in this type of chain, and in which further said lengthening and shortening means is prevented when in use from causing uncoupling of the chain, the improvedchain at the same time being stronger and more flexible in construction, or superior ornamental effect, and of low cost to manufacture.

According to the present invention a suspension chain is furnished in which alternate links are of externally grooved formation each having an inward embossment of substantially hemispherical conformation at one end, which embossment is cut through transversely to provide an open-ended link. These open-ended inwardly embossed alternate links are assembled in conjunction curvature in two directions at right angles,

thereby providing both for the lateral closing action, and at the same time for a kind of pivotal ball-and-socketconnection which is freely and flexibly movable in any direction. The internal grooves of the intermediate closed links further providea means of more effectively enclosing and protecting the crossed and interthreaded parts of the electric leads.

In order that this invention may be clearly understood and readily carried into practice, reference may be had to the appended explanatory sheet of drawings, upon which z Figure 1 is a front elevation of a length of suspension chain in accordance with the invention and showing also the crossed and interthreaded electric leads.

Figure 2 is a side elevation of Figure 1.

Figure 3 is a sectional front elevation of the chain shown in Figures 1 and 2.

Figure 4: is a perspective view of the open-ended externally-grooved link shown in Figures 1 to 3.

Figure 5 is a perspective view of a length of suspension chain in a modified form.

Figure 6 is a perspective view of the open-ended externally-grooved link shown, in Figure 5.

Figure 7 is a perspective view of a pair of links in which the complementary closed link is of a modified form.

Figure 8 is a perspective view of a length of suspension chain in a further modified form.

Figures 9 and 10 are perspective views of further modified forms of the complementary elosedlink.

In a convenient embodiment of the invention, Figures 1 to 4, alternate links a of the suspension chain are of seamless construction pressed or otherwise worked into an externally grooved formation of substantially semi-circular and externally concave cross section, one end of said externally grooved link being further pressed by means of a suitable tool or die to form an inward embossment a oi substantially hemispherical conformation, which embossment a is cut through transversely at a to provide an open-ended link. The intermediate complementary links 6 are likewise of seamless con struction but are pressed into an internally grooved formation of substantially semi-circular and externally convex cross-section, the alternate open-ended links a having a detachable and universally flexible locking connection to these intermediate complementary links l) as hereinbefore described. 0 are the electric leads, the crossed and interthreaded parts of which are partly enclosed and concealed and effectively protected by the external grooves of the alternate open-ended links a in cooperation with the internal grooves of the intermediate complementary closed links I).

In a modified embodiment of the invention, Figures 5 and 6, the externally grooved alternate links a are formed with an in ward embossment a at both ends, one only of which embossments a is cut through at u? to provide the O1311-11Cll link.

In a further modification, Figure 7, the internally grooved intermediate eomplementary links 5 are formed with a contracted waist part b which still more effectively encloses and protects the crossed and interthreaded parts of the electric leads.

In further modifications, Figures 8, 9 and 10, the intermediate complementary links If, instead of being internally grooved, may be 01' llat seamless construction with one (Figures S and 9) or both (Figure 10) of its semi-circular ends cut longitudinally to a short distance and expanded at Z) to provide a terminal aperture or apertures b into which the embossment or embossments a of the open-ended links are adapted to be passed, the expanded sides 7) of said terminal aperture or apertures being suitably bent or ted to provide a detachable locking engap ment with the embossment or emboss meets a? in a manner similar to that hereinbe'l ore described.

vl hat I claim as my invention and desire to secure by Letters Patent is In a chain of the class described, a sheet metal link of concavo-convei; cross section, arranged with the concave side outermost, and a sheet metal link of concave-convex cross section, engaged with the first named link and arranged with the concave side innermost, the first named link having aboss on its inner side at the point of engagement, said boss fitting in the concave side of the last named link and efl'ecting a pivotal connection between the links.

In witness whereof l have hereunto set my hand.

it'll-NEST JOSEPH PERRY. 

